#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>

int main() {
    int a, b, c;
    scanf("%d %d %d", &a, &b, &c);
    float avg = (a + b + c) / 3;
    if (avg >= 60)
        printf("NO");
    else
        printf("YES");
    return 0;
}